Let's divide 65879853 by 123
The aim is to understand the frequency of 123 in 65879853.

Step 1:
When dividing 6 by 123, we get 0 with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Fetch the next digit (5) from the dividend, attach it to 6 and continue: 65 / 123

Going ahead to step 2:
123 goes into 65 0 times with a remainder of 65.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 65, we end up with 65.
Take the next digit (8) from the dividend and append it to 65, then repeat: 658 / 123

Let's proceed to step 3:
123 goes into 658 5 times with a remainder of 43.
The next digit of our result is 5. 
Result so far: 5.0
If we take 615 away from 658, we end up with 43.
Include the next digit (7) from the dividend after 43, then repeat: 437 / 123

Let's proceed to step 4:
123 can be fit into 437 3 times, resulting in a remainder of 68.
Put 3 as the next digit of the answer. 
Result so far: 53.0
If we take 369 away from 437, we end up with 68.
Append the next digit (9) from the dividend to 68 and continue with: 689 / 123

Advancing to step 5:
123 can be fit into 689 5 times, resulting in a remainder of 74.
Use 5 as the next digit of our solution. 
Result so far: 535.0
Subtract 615 from 689 to get 74.
Grab the next digit (8) from the dividend, add it to 74, then carry on: 748 / 123

On to step 6:
123 can be fit into 748 6 times, resulting in a remainder of 10.
The number 6 becomes the next digit in our result. 
Result so far: 5356.0
Subtract 738 from 748 to get 10.
Grab the next digit (5) from the dividend, add it to 10, then carry on: 105 / 123

On to step 7:
The number 123 fits into 105 0 times, leaving a remainder of 105.
Put 0 as the next digit of the answer. 
Result so far: 53560.0
If we subtract 0 from 105, we get 105.
Take the next digit (3) from the dividend and append it to 105, then repeat: 1053 / 123

Let's proceed to step 8:
When dividing 1053 by 123, we get 8 with a remainder of 69.
Record the quotient 8 as the next digit in the result. 
Result so far: 535608.0
Subtracting 984 from 1053 leaves us with 69.
Since there are no more digits in the dividend, we add a zero to the remainder making it 690, and continue the process.

Moving on to step 9:
123 can be fit into 690 5 times, resulting in a remainder of 75.
Put 5 as the next digit of the answer. 
Result so far: 535608.5
If we subtract 615 from 690, we get 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Advancing to step 10:
750 divided by 123 is 6 with a remainder of 12.
The next digit of our result is 6. 
Result so far: 535608.56
Subtract 738 from 750 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 11:
The number 123 fits into 120 0 times, leaving a remainder of 120.
The number 0 becomes the next digit in our result. 
Result so far: 535608.56
If we take 0 away from 120, we end up with 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Going ahead to step 12:
123 goes into 1200 9 times with a remainder of 93.
The next digit of our result is 9. 
Result so far: 535608.5609
If we subtract 1107 from 1200, we get 93.
Since there are no more digits in the dividend, we add a zero to the remainder making it 930, and continue the process.

On to step 13:
When dividing 930 by 123, we get 7 with a remainder of 69.
Use 7 as the next digit of our solution. 
Result so far: 535608.56097
Subtract 861 from 930 to get 69.
Since there are no more digits in the dividend, we add a zero to the remainder making it 690, and continue the process.

On to step 14:
690 divided by 123 is 5 with a remainder of 75.
Put 5 as the next digit of the answer. 
Result so far: 535608.560975
The remainder is 75 after subtracting 615 from 690.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Advancing to step 15:
123 goes into 750 6 times with a remainder of 12.
Write down 6 as next digit of the result. 
Result so far: 535608.5609756
Subtract 738 from 750 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Let's proceed to step 16:
123 goes into 120 0 times with a remainder of 120.
The next digit of our result is 0. 
Result so far: 535608.5609756
Subtract 0 from 120 to get 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

The final outcome is 535608.5609756, with a leftover of 1.2e-07.